Tributes continue to pour in for police constable Keith Palmer who died after being stabbed in an horrific series of "terrorist" events in Westminster.
48-year-old PC Palmer was on duty outside the Palace of Westminster when he was stabbed by a man in an "Islamist act of terrorism" on Wednesday (March 22).
Three others have been named dead, including the attacker who was shot by officers and around forty others were injured, with 29 still being treated this morning and seven in a critical condition.
The father and husband was a member of the Parliamentary and Diplomatic Protection Squad, with 15 years service.
"Heartbroken" former colleague, Conservative MP James Cleverly, paid tribute to the "lovely man" he had known for a quarter of a century.
Writing on Twitter, he said: "I've known Keith for 25 years. We served together in the Royal Artillery before he became a copper.
"A lovely man, a friend. I'm heartbroken.
"My thoughts are with the family, friends and colleagues of Pc Keith Palmer. A brave man."
Scotland Yard's top anti-terror officer Mark Rowley said of his colleague: "He was someone who left for work today expecting to return home at the end of his shift - and he had every right to expect that would happen."
He added this morning (Thursday March 23): "Tragically the deaths included PC Keith Palmer who was protecting Parliament, and two members of the public - a woman aged in her mid 40’s and a man aged in his mid 50’s.
"The fourth man of course was the terrorist who was shot dead by armed police at the scene."
The Metropolitan Police Federation, which represents officers from the force, said: "PC Keith Palmer. Our brave Met #Police colleague who today made the ultimate sacrifice #LestWeForget"
In solidarity with London
The Eiffel Tower went dark last night in solidarity with London following the events.
It switched off its lights as the clock struck midnight, hours after the UK suffered its worst attack since 2005.
Seven arrested as Westminster remains closed for investigation
Six addresses have been raided overnight in Birmingham and London, with seven people arrested.
A Metropolitan police spokesman said: "Hundreds of detectives have been working through the night and during that time I can confirm we have searched six addresses - and made seven arrests.
"The inquiries in Birmingham, London and other parts of the country continue.
"It is still our belief - which continues to be born out by our investigation - that this attacker acted alone yesterday and was inspired by international terrorism.
"To be explicit - at this stage, we have no specific information about further threats to the public.
"Clearly our investigation is ongoing - developing all the time - and is focused on his motivation, his preparation and associates.
"The large and complicated crime scene remains in place and our work there continues - I would like to thank everyone for their support and patience as we finish this work."
Extra armed and unarmed police will be in London and across transport systems in the country as the threat levels remain severe.
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